|Publication number||US7739912 B2|
|Application number||US 11/245,883|
|Publication date||Jun 22, 2010|
|Filing date||Oct 7, 2005|
|Priority date||Oct 7, 2004|
|Also published as||US8601876, US20070258628, US20100251824, US20140090473, WO2006042144A2, WO2006042144A3|
|Publication number||11245883, 245883, US 7739912 B2, US 7739912B2, US-B2-7739912, US7739912 B2, US7739912B2|
|Inventors||John K. Schneider, Jack C. Kitchens, James T. Baker|
|Original Assignee||Ultra-Scan Corporation|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (33), Non-Patent Citations (1), Referenced by (3), Classifications (17), Legal Events (3)|
|External Links: USPTO, USPTO Assignment, Espacenet|
This application claims the benefit of priority to U.S. provisional patent application Ser. No. 60/616,953, filed on Oct. 7, 2004.
The present invention relates to ultrasonic biometric readers, such as fingerprint scanners.
Since the 1800's fingerprint information has been collected from human fingers and hands by means of ink and paper. For the purposes of this document, the term “fingerprint” is used to mean the skin surface friction ridge detail of a portion of a hand, such as a single fingerprint, or the entire hand. In recent years various electronic fingerprint scanning systems have been developed utilizing optical, capacitance, direct pressure, thermal and ultrasonic methods. Methods based on ultrasound have proven to be highly accurate, since they are insulated from the effects of grease, dirt, paint, ink and other image contaminants.
In an ultrasonic system, a piezoelectric transducer may be used to send an ultrasonic wave through an ultrasound transmitting media. The dimensions of prior art ultrasonic scanners and the ultrasound emitters used in those prior art scanners are such that the emitter produces a wave that emanates from a small location, and therefore, the emitters used in the prior art devices may be thought of as point sources of the ultrasound energy.
In ultrasonic fingerprint scanners, the ultrasound wave is started and stopped to produce a pulse. At each material interface encountered by the pulse, a portion of the pulse reflects. For example, the interface between a platen and skin or the interface between air and skin may each reflect a portion of the pulse. The fraction of ultrasound reflected is a function of differences in impedance between the two materials comprising the interface. The fraction of ultrasound reflected can be calculated by the equation, R=((Z1−Z2)/(Z1+Z2))2, where R is the fraction of sound reflected, Z1 is the acoustic impedance of the first material and Z2 is the acoustic impedance of the second material. Acoustic impedance is a measure of a material's resistance to the propagation of ultrasound. Acoustic impedance, Z, is defined as Z=r·c, where r is the material density, and c is the longitudinal propagation velocity of ultrasound in the material. The larger the change in acoustic impedance, the larger the fraction reflected.
The reflected wave pulses may be detected by a detector. The elapsed time during which the pulse traveled from the ultrasound pulse emitter to the interface and back may be determined. The elapsed time may be used to determine the distances traveled by the pulse and its reflected wave pulses. By knowing the distance traveled, the position of an interface may be determined.
There may be many interfaces encountered by the emitted pulse, and so there may be many reflected wave pulses. Since it is the interfaces associated with a finger that are of interest in generating an image of a fingerprint, it may be necessary to identify those reflected wave pulses that are associated with the finger. The approximate position of a finger being scanned may be known, and therefore the pulse reflected from the finger may be expected during a particular time interval. In a technique commonly referred to as “range gating”, a detector may be configured to ignore reflected pulses that are not received during that time interval. The reflected signals associated with the finger may be processed and converted to a digital value representing the signal strength. The digital value may be used to produce a graphical display of the signal strength, for example by converting the digital values to a gray-scale bitmap image, thereby producing a contour map of the finger surface which is representative of the depth of the ridge structure detail.
Although using ultrasound to produce an image of a fingerprint may be superior in detail to a similar image collected by an optical system or other means, existing ultrasound systems have deficiencies. Collecting information using an ultrasound transducer is usually accomplished by moving the ultrasound transducer side-to-side while advancing the transducer in a direction that is different from the side-to-side motion. Such an arrangement is commonly referred to as a raster scanning process. As the raster scanning process proceeds, the ultrasound raster scanning mechanism collects each pixel of image information individually, and records those pixels for use in generating an image of the fingerprint. The time required to collect a raster scanned ultrasonic image may be longer than the time needed to collect an optical image of the same size. Consequently, there is a need for a faster ultrasound scanner.
The present invention relates to a device and method of capturing a fingerprint image representing the friction ridge surface of a finger. A platen may be provided and a user may place his finger on the platen in order to permit information to be gathered which may be used to create an image of the fingerprint. A plane pulse-wave generator may generate an ultrasound wave pulse and an ultrasonic wave detector may be used to receive reflected ultrasound signals. The plane pulse-wave generator may be located between the receiving device and the platen.
A phased array of piezoelectric transducer elements can be used to both steer and focus an ultrasound pulse to a target area pixel in a raster scanning process. This may be attractive from a manufacturing perspective in that it may allow the electronic focusing and steering of an ultrasound pulse and avoid the mechanical positioning and alignment required in present ultrasound scanning systems.
In an embodiment of the invention, a platen and a finger may receive ultrasonic wave energy and the reflected energy may be detected and converted to an image of the finger by means of an array of detecting elements. In a line array configuration, information about the fingerprint may be acquired by moving the line array detector and collecting image information one line at a time. A line area detector may be used with a line array generator or an area array generator. A system without moving components may be constructed and the finger may be dragged across the platen to allow the image to be collected. Alternatively, by providing an area array detector and an area array generator, an image may be obtained faster, and the user need not be required to move his finger in order to facilitate image collection.
A fingerprint scanning system is disclosed herein which may be used to measure and image the friction ridge surface of a finger, to obtain an image that is representative of the ridge and valley structure of the skin on the finger. The scanning system may have (a) an imaging surface (sometimes referred to as a platen), which may be a substantially flat piece of polished polycarbonate, that contacts the finger or fingers being imaged, and (b) a device for accurately measuring the relief profile of a skin surface that is in contact with the imaging surface by means of ultrasound transmitting and detecting devices and techniques. It should be noted that the embodiments described in this document are not meant to limit the scope of the invention. Further, each embodiment described in this document may function in either a direct reading mode or as a phased array mode.
The invention will now be described by way of non-limiting examples, with reference to the attached drawings and diagrams in which:
The invention may be embodied as a fingerprint scanner 10. Such a scanner 10 may have an ultrasonic wave detector 13, a platen 16 and an ultrasonic wave generator 19 located between the detector 13 and the platen 16. The generator 19 may include a piezoelectric film 22. Pulse waves may be generated by applying a voltage to the piezoelectric film 22 to expand or contract the film 22, depending upon the charge applied, to generate a plane pulse-wave. The voltage may be applied to the film 22 via a first electrode 28 and a second electrode 31. In this fashion, an ultrasound wave pulse may be made by changing the volume occupied by the film. This pulse-wave travels toward the finger, passes through the platen 16, and is reflected from the finger 25, passes back through the platen 16, through the first electrode 28, film 22, and second electrode 31 until it strikes the detector 13.
The detector 13 and the generator 19 may be separated. A fluidic transmission medium 33 may be located between the detector 13 and the generator 19. Suitable fluidic transmission media 33 may have very different viscosities, relative to each other. For example, one suitable fluidic transmission medium 33 may be mineral oil. Another suitable fluidic transmission medium 33 may be a gel comprised of vinyl plastisol. Using a gel may have an advantage over less viscous transmission media 33 because a gel is less prone to leak out of the scanner 10. For ease of reference, the term “fluidic transmission medium” is used to include many types of materials, including those that are commonly described as gels.
In prior art systems discrete transducer elements are used to both emit and detect an ultrasound pulse. Arrays of these discrete transducer elements are often used, and such arrays create wave interference problems as a result of the discretely generated point sources of the wave pulses. The waves from transducers in the array can intersect and both nullify or amplify each other as they interfere.
Since the piezoelectric film 22 may reside substantially in a plane, the wave generated by the film 22 may be used to generate a wave that emanates in a planar fashion.
An array that might be used in a prior art device for the discrete element transmitter/receiver could be used in the invention as a detector 13. In such an embodiment, the emitter capability of such a transducer would not be used. Additionally, a receive-only array that may be more fragile in construction than the transmit/receive array could also be used. Such arrays, both rugged and fragile types, are available from commercial sources and although not specifically designed for fingerprinting systems are suitable for use in the invention as a detector 13.
The embodiment shown in
The embodiment of
The wheel 43 may be rotated so as to move the line array detector 13 in an angular fashion in a plane that is substantially parallel to the platen 16. In this embodiment, the detector 13 may be angularly swept in a circle in order to gather data about the finger 25. While sweeping in an angular fashion, the detector 13 may be moved in a plane that is substantially parallel to the platen 16, or substantially parallel to the generator 19, or both.
The embodiment shown in
The carriage 67 may have mounted thereon a line array ultrasound detector 13 and a plane pulse-wave generator 19. The generator 19 may have a width that is only one pixel wide and a length that is more than 50 pixels, to provide a length-to-width ratio greater than 50. The carriage 67 may be translated near the platen 16 and submerged in a fluidic ultrasound transmitting medium 33, such as mineral oil. Such a system may be programmed to acquire image information in either or both, directions of travel.
It should be noted that the embodiments of
The invention may be embodied as a method.
The method may be carried out such that sending the ultrasound wave pulse includes expanding a film, such as the piezoelectric film described above. In such a method, the film may be expanded by applying a voltage difference across the film.
The detector may be moved relative to the platen in order to receive reflected ultrasound wave pulses from different parts of the finger. In this manner, information about different parts of the finger may be gathered by the detector and used to produce an image of the finger. For example, the detector may be moved angularly in a plane that is substantially parallel to the platen. In another embodiment of the invention, the detector may be moved arcuately about an axis that is parallel to the platen. The detector may also be moved linearly.
U.S. provisional patent application No. 60/616,953 includes descriptions of embodiments according to the invention. Application 60/616,953 is incorporated herein by reference.
Although the present invention has been described with respect to one or more particular embodiments, it will be understood that other embodiments of the present invention may be made without departing from the spirit and scope of the present invention. Hence, the present invention is deemed limited only by the appended claims and the reasonable interpretation thereof.
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US4395652 *||Sep 11, 1980||Jul 26, 1983||Toray Industries, Inc.||Ultrasonic transducer element|
|US4718421 *||Jul 28, 1986||Jan 12, 1988||Siemens Aktiengesellschaft||Ultrasound generator|
|US4977601||Mar 26, 1987||Dec 11, 1990||Werner Pritzl||Method of recognizing a fingerprint|
|US5177353||Jul 11, 1991||Jan 5, 1993||Retrievex, Inc.||Finger surface image enhancement having liquid layer on finger touching surface of the plate|
|US5483963||Jul 22, 1994||Jan 16, 1996||Loral Infrared & Imaging Systems, Inc.||Two dimensional transducer integrated circuit|
|US5551295||Jun 29, 1993||Sep 3, 1996||Stockburger; Hermann||Method and apparatus using ultrasonic and light waves for identification of test specimens|
|US5563345||Apr 18, 1994||Oct 8, 1996||Jenoptik Gmbh||Device for ultrasonic identification of fingerprints|
|US5647364 *||Feb 15, 1995||Jul 15, 1997||Ultra-Scan Corporation||Ultrasonic biometric imaging and identity verification system|
|US5737439||Oct 29, 1996||Apr 7, 1998||Smarttouch, Llc.||Anti-fraud biometric scanner that accurately detects blood flow|
|US6078265||Feb 11, 1998||Jun 20, 2000||Nettel Technologies, Inc.||Fingerprint identification security system|
|US6219439||Jul 9, 1999||Apr 17, 2001||Paul M. Burger||Biometric authentication system|
|US6310371||Oct 8, 1999||Oct 30, 2001||United Microelectronics Corp.||Fingerprint sensor chip|
|US6317508||Jan 13, 1998||Nov 13, 2001||Stmicroelectronics, Inc.||Scanning capacitive semiconductor fingerprint detector|
|US6552841||Jan 7, 2000||Apr 22, 2003||Imperium Advanced Ultrasonic Imaging||Ultrasonic imager|
|US6628377||Apr 4, 2000||Sep 30, 2003||Stmicroelectronics, Inc.||Scanning optical semiconductor fingerprint detector|
|US6720712||Mar 23, 2001||Apr 13, 2004||Cross Match Technologies, Inc.||Piezoelectric identification device and applications thereof|
|US6812621||Jul 21, 2003||Nov 2, 2004||Cross Match Technologies, Inc.||Multiplexer for a piezo ceramic identification device|
|US6971991||Mar 7, 2003||Dec 6, 2005||Imperium, Inc.||Apparatus for multimodal plane wave ultrasound imaging|
|US20030156740||Oct 30, 2002||Aug 21, 2003||Cross Match Technologies, Inc.||Personal identification device using bi-directional authorization for access control|
|US20030158819||Oct 31, 2002||Aug 21, 2003||Cross Match Technologies, Inc||Personal identification device and system used to produce and organize digital receipts|
|US20030229506||Oct 31, 2002||Dec 11, 2003||Cross Match Technologies, Inc.||System and method that provides access control and monitoring of consumers using mass transit systems|
|US20030229811||Oct 30, 2002||Dec 11, 2003||Cross Match Technologies, Inc.||Method that provides multi-tiered authorization and identification|
|US20040140735||Jul 29, 2003||Jul 22, 2004||Cross Match Technologies, Inc.||Biometric sensing device with isolated piezo ceramic elements|
|US20050063571||Sep 3, 2004||Mar 24, 2005||Authentec, Inc.||Electronic device including optical dispersion finger sensor and associated methods|
|US20050063572||Sep 3, 2004||Mar 24, 2005||Authentec, Inc.||Finger sensor using optical dispersion sensing and associated methods|
|US20050063573||Sep 3, 2004||Mar 24, 2005||Authentec, Inc.||Multi-biometric finger sensor including optical dispersion sensing pixels and associated methods|
|US20050089203||Sep 3, 2004||Apr 28, 2005||Authentec, Inc.||Multi-biometric finger sensor using different biometrics having different selectivities and associated methods|
|US20050094855||Oct 29, 2003||May 5, 2005||Proano Cesar H.||Fingerprint imaging using a flat panel detector|
|US20050105784||Aug 30, 2004||May 19, 2005||Samsung Electronics Co., Ltd.||Fingerprint sensor and fabrication method thereof|
|US20050123176||Nov 24, 2004||Jun 9, 2005||Canon Kabushiki Kaisha||Fingerprint reading device and personal verification system|
|US20050141048||Mar 19, 2003||Jun 30, 2005||Casio Computer Co., Ltd||Image reading apparatus and drive control method therefor|
|US20050163353 *||Jan 21, 2005||Jul 28, 2005||Ultra-Scan Corporation||Fingerprint scanner and method having an acoustic detector|
|US20060173316 *||Oct 17, 2005||Aug 3, 2006||Schneider John K||Hand scanner with moveable platen|
|1||International Search Report For PCT/US05/36219, May 8, 2007, Ultra-Scan Corporation.|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US8781180||Mar 19, 2012||Jul 15, 2014||Qualcomm Incorporated||Biometric scanner with waveguide array|
|US8890853||Jan 11, 2013||Nov 18, 2014||Sharp Laboratories Of America, Inc.||In-pixel ultrasonic touch sensor for display applications|
|US8977013||Jul 12, 2011||Mar 10, 2015||The Institute For Diagnostic Imaging Research, University Of Windsor||Biometric sensor and method for generating a three-dimensional representation of a portion of a finger|
|U.S. Classification||73/620, 382/124, 73/622, 73/603|
|International Classification||G01N29/00, G06K9/00|
|Cooperative Classification||A61B8/0858, A61B8/4483, G06K9/00026, A61B5/1172, G01N29/2437, G06K9/0002|
|European Classification||A61B8/44R, A61B5/117B, G06K9/00A1C, A61B8/08J, G06K9/00A1A|
|Nov 21, 2005||AS||Assignment|
Owner name: ULTRA-SCAN CORPORATION, NEW YORK
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:SCHNEIDER, JOHN K.;KITCHENS, JACK C.;BAKER, JAMES T.;REEL/FRAME:017233/0795;SIGNING DATES FROM 20051010 TO 20051012
Owner name: ULTRA-SCAN CORPORATION,NEW YORK
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:SCHNEIDER, JOHN K.;KITCHENS, JACK C.;BAKER, JAMES T.;SIGNING DATES FROM 20051010 TO 20051012;REEL/FRAME:017233/0795
|May 14, 2013||AS||Assignment|
Owner name: QUALCOMM INCORPORATED, CALIFORNIA
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:ULTRA-SCAN CORPORATION;REEL/FRAME:030416/0069
Effective date: 20130507
|Nov 26, 2013||FPAY||Fee payment|
Year of fee payment: 4